Mar. 11, 2011

Science Diction: The Origin Of The Word 'Clone'

In 1903, plant physiologist Herbert J. Webber coined the term 'clone,' from the Greek klon, to refer to the technique of propagating new plants using cuttings, bulbs or buds. Science historian Howard Markel discusses how the term later came to refer to a bevy of genetic manipulations.

The word clone, literally, has its roots in the ground.

At the turn of the last century, agricultural science was hitting its stride and developing new breeding techniques to produce large crops. In 1903, Herbert J. Webber, a plant physiologist at the U.S. Department of Agriculture, set out to describe one such technique where plants were "propagated vegetatively (asexually from a single progenitor) by buds, grafts, cuttings, suckers, runners, slips, bulbs, tubers, etc."

Webber felt strongly that "words that we expect to be generally used…should be short, euphonious, phonetically spelled, easily pronounced, and different from any other word in ordinary use so that it will not suggest any other meaning than the one desired."

As a result, he chose the Greek klon, which means a twig, spray, or slip of a plant that is broken off for the purposes of propagation. Klon, incidentally, beat out some of the other words he was considering at the time such as "strace"—a combination of strain and race, and two other Greek words for young branches or twigs, klados and klema which were, in Webber’s opinion, too clumsy.

In 1905, when the Association of Agricultural Colleges and Experiment Stations formally adopted the term, a silent "e" was added to the word for purposes of conformity to the English language.

Clone may well have remained an agricultural term had it not been so avidly picked up by science fiction writers.

For example, Aldous Huxley alluded to cloning in his 1932 novel, Brave New World. Huxley fans will recall a process he called "Bokanovskification" [after the fictional scientist who invented the procedure] whereby human embryos were split to mass-produce identical drones, which Huxley called Gamma, Deltas and Epsilons. The drones performed menial labor and were subservient to Alphas and Betas, who were biologically engineered to be physically and intellectually superior. 38 years later, in 1970, Alvin Toffler published his best-selling book, Future Shock, in which he predicted that someday "man will be able to make biological carbon copies of himself." And in 1976, Ira Levin’s novel, The Boys From Brazil, told the hair-raising tale of a plan to clone Adolf Hitler’s remains in order to reproduce and raise dozens of little Fuehrers around the world.

The word "clone" firmly entered the realm of genetics in the 1960s when scientists such as J.B.S. Haldane and Joshua Lederberg predicted the development of nuclear transplantation for higher species of animals. Both men presciently warned about the ramifications of human cloning, including the ethical conundrums arising from those who would want to reproduce themselves for a variety of socially unacceptable purposes.

Matters became even more confusing—and controversial—in recent decades, as the word 'cloning' came to serve as an umbrella term to describe a number of different processes for duplicating biological material.

The 3 major techniques of cloning are:

Recombinant DNA technology or DNA cloning, a method for replicating a DNA fragment of interest

Reproductive cloning, used to generate an animal with the same nuclear DNA as another currently or previously existing animal, such as Dolly the sheep

Therapeutic or embryo cloning, a technique for creating and harvesting embryonic stem cells to study human development and treat disease

In recent years, cloning has become a hot-button issue in the culture wars over abortion, in vitro fertilization techniques, and stem cell biology, even though those arguing about it are not always talking about the same thing.

And it all began with a euphonious term for a twig of a plant that was coined for the sake of clarity, proving once again that even the best laid plans often go awry.